Read all of this leaflet carefully before you start taking this medicine - Body weight: You should monitor your child’s weight every month and
because it contains important information for you.
see your doctor as soon as possible if your child is not gaining enough
- Keep this leaflet. You may need to read it again.
weight. Zonisamide is not recommended for children who are
- If you have any further questions, ask your doctor or pharmacist.
underweight or have a small appetite, and should be used with
- This medicine has been prescribed for you only. Do not pass it on to
caution in those below 20 kg.
others. It may harm them, even if their signs of illness are the same as - Increased acid level in the blood and kidney stones: Reduce these risks
yours.
by ensuring that your child drinks enough water and is not taking any
- If you get any side effects, talk to your doctor or pharmacist. This
other medicine which could cause kidney stones (see Other medicines
includes any possible side effects not listed in this leaflet. See section 4.
and Zonisamide). Your doctor will monitor your child’s blood
bicarbonate levels and kidneys (see also section 4).
What is in this leaflet
1. What Zonisamide is and what it is used for
Do not give this medicine to children below the age of 6 years because it
2. What you need to know before you take Zonisamide
is not known for this age group whether the potential benefits are greater
3. How to take Zonisamide
than the risks.
4. Possible side effects
5. How to store Zonisamide
Other medicines and Zonisamide
6. Contents of the pack and other information
Tell your doctor or pharmacist if you are taking, have recently taken or
might take any other medicines.
1. What Zonisamide is and what it is used for
- Zonisamide should be used carefully in adults when taken with
medicines that can cause kidney stones, like topiramate or
The full name of this medicine is Zonisamide Dr. Reddy's 25 mg, 50 mg
acetazolamide. In children, this combination is not recommended.
and 100 mg Hard Capsules but will be referred to as Zonisamide
- Zonisamide could possibly increase your blood levels of medicines like
throughout this leaflet.
digoxin and quinidine, and so a reduction in their dose may be
required.
Zonisamide capsules contain the active substance zonisamide, and are
- Other medicines like phenytoin, carbamazepine, phenobarbitone and
used as an antiepileptic medicine.
rifampicin can decrease your blood levels of zonisamide, which may
Zonisamide is used to treat seizures that affect one part of the brain
require an adjustment of your dose of Zonisamide.
(partial seizure), which may or may not be followed by a seizure affecting
all of the brain (secondary generalisation).
Zonisamide with food and drink
Zonisamide can be taken with or without food.
Zonisamide may be used:
- On its own to treat seizures in adults.
Pregnancy and breast-feeding and fertility
- With other antiepileptic medicines to treat seizures in adults,
If you are a woman of childbearing age you must use adequate
adolescents, and children aged 6 years and above.
contraception while taking and for one month after stopping Zonisamide.
2. What you need to know before you take Zonisamide

Tell your doctor immediately if you might be, or are pregnant, or are
planning to get pregnant. You must only take Zonisamide during your
pregnancy if your doctor tells you to. Research has shown an increased
risk of birth defects in children of women taking anti-epileptic medicines.

380 mm

Do not take Zonisamide:
- if you are allergic to zonisamide or any of the other ingredients of this
medicine (listed in section 6).
- if you are allergic to other sulphonamide medicines. Examples include:
Do not breastfeed whilst taking, or for one month after stopping
sulphonamide antibiotics, thiazide diuretics, and sulfonylurea
Zonisamide.
antidiabetes medicines.
Warnings and precautions
Zonisamide belongs to a group of medicines (sulphonamides) which can
cause severe allergic reactions, severe skin rashes, and blood disorders,
which very rarely can be fatal (see section 4. Possible side effects)
Serious rashes occur in association with Zonisamide therapy,
including cases of Stevens-Johnson syndrome.
Talk to your doctor or pharmacist before taking Zonisamide
- if you are younger than 12 years old, as you may be at greater risk of
decreased sweating, heat stroke, pneumonia and liver problems. If you
are younger than 6 years old, Zonisamide is not recommended for you.
- if you are elderly, as your dose of Zonisamide may need adjusting, and
you may be more likely to develop an allergic reaction, severe skin rash,
swelling of the feet and legs, and itchiness when taking Zonisamide
(see section 4 Possible side effects).
- if you suffer from liver problems, as your dose of Zonisamide may need
adjusting.
- if you suffer from kidney problems as your dose of Zonisamide may
need adjusting.
- if you have previously suffered from kidney stones, as you may be at
increased risk of developing more kidney stones. Reduce the risk of
kidney stones by drinking sufficient water.
- if you live in a place or are on holiday in a place where the weather is
warm. Zonisamide can make you perspire less, which can cause your
body temperature to increase. Reduce the risk of overheating by
drinking sufficient water and keeping cool.
- if you are underweight, or have lost a lot of weight as Zonisamide can
cause you to lose more weight. Tell your doctor as this may need to be
monitored.
If any of these applies to you, tell your doctor before you take Zonisamide.
Children and adolescents
Talk to your doctor about the following risks:
Preventing overheating and dehydration in children
Zonisamide can cause your child to sweat less and overheat and if your
child is not treated this can lead to brain damage and death.
Children are most at risk especially in hot weather.
When your child is taking Zonisamide:
- Keep your child cool especially in hot weather
- Your child must avoid heavy exercise especially when the weather is
hot
- Give your child plenty of cold water to drink
- Your child must not take these medicines:
carbonic anhydrase inhibitors (like topiramate and acetazolamide),
and anticholinergic agents (like clomipramine, hydroxyzine,
diphenhydramine, haloperidol, imipramine and oxybutynin).
If your child’s skin feels very hot with little or no sweating, becomes
confused, has muscle cramps, or your child’s heartbeat or breathing
becomes rapid:
- Take your child to a cool, shaded place
- Sponge your child’s skin with cool (not cold) water
- Give your child cold water to drink
- Seek urgent medical assistance.

There are no clinical data available on the effects of zonisamide on human
fertility. Studies in animals have shown changes in fertility parameters.
Driving and using machines
Zonisamide may affect your concentration, ability to react/respond, and
may make you feel sleepy, particularly at the beginning of your treatment
or after your dose is increased. Be especially careful while driving or
operating machinery, if Zonisamide affects you in this way.
3. How to take Zonisamide
Always take this medicine exactly as your doctor has told you. Check with
your doctor or pharmacist if you are not sure.
The usual adult dose
When you take Zonisamide on its own:
- The starting dose is 100 mg taken once a day.
- This may be increased by up to 100 mg at intervals of two weeks.
- The recommended dose is 300 mg once a day.
When you take Zonisamide with other antiepileptic medicines:
- The starting dose is 50 mg daily taken in two equal doses of 25 mg.
- This may be increased by up to 100 mg at intervals of one to two
weeks.
- The recommended daily dose is between 300 mg and 500 mg.
- Some people respond to lower doses. The dose may be increased
more slowly if you experience side effects, are elderly or if you suffer
from kidney or liver problems.
Use in children and adolescents
Use in children (aged 6 to 11 years) and adolescents (aged 12 to 17 years)
weighing at least 20 kg:
- The starting dose is 1 mg per kg of body weight taken once a day.
- This may be increased by 1 mg per kg of body weight at intervals of
one to two weeks.
- The recommended daily dose is 6 to 8 mg per kg for a child with a
body weight of up to 55 kg or 300 to 500 mg for a child with a body
weight more than 55 kg (which ever dose is lower) taken once a day.
Example: A child who weighs 25 kg should take 25 mg once a day for the first
week, and then increase the daily dose by 25 mg at the start of each week
until a daily dose between 150 to 200 mg is reached.
If you feel that the effect of Zonisamide is too strong or too weak, talk to
your doctor or pharmacist.

- Zonisamide capsules must be swallowed whole with water.
- Do not chew the capsules.
- Zonisamide can be taken once or twice daily, as instructed by your
doctor.
- It you take Zonisamide twice a day, take half the daily dose in the
morning and half in the evening.
If you take more Zonisamide than you should
If you may have taken more Zonisamide than you should, tell a carer
(relative or friend), your doctor or pharmacist immediately, or contact your
nearest hospital casualty department, taking your medicine with you. You
may become sleepy and could lose consciousness. You might also feel sick,
have a sore stomach, muscle twitches, eye movement, feel faint, have a
slowed heart beat, and reduced breathing and kidney function.
Do not try to drive.
If you forget to take Zonisamide
If you forget to take a dose, don’t worry: take the next dose when it is due.
Do not take a double dose to make up for a forgotten dose.
If you stop taking Zonisamide
Zonisamide is meant to be taken as a long-term medicine. Do not reduce
your dose or stop your medicine unless your doctor tells you to.
If your doctor advises you to stop taking Zonisamide your dose will be
reduced gradually to lower the risk of more seizures.
If you have any further questions on the use of this medicine, ask your
doctor or pharmacist.
4. Possible side effects
Like all medicines, this medicine can cause side effects, although not
everybody gets them.
Zonisamide belongs to a group of medicines (sulphonamides) that can
cause severe allergic reactions, severe skin rashes, and blood disorders,
which very rarely can be fatal.
Contact your doctor immediately if you:
- have difficulty breathing, a swollen face, lips or tongue, or a severe skin
rash as these symptoms may indicate that you are having a severe
allergic reaction.
- have signs of overheating - high body temperature but little or no
sweating, rapid heartbeat and breathing, muscle cramps, and confusion.
- have thoughts of harming or killing yourself. A small number of people
being treated with anti- epileptics such as Zonisamide have had
thoughts of harming or killing themselves.
- have pain in your muscles or a feeling of weakness, as this may be a sign
of abnormal muscle breakdown which can lead to kidney problems.
- get a sudden pain in your back or stomach, have pain on urinating
(passing water) or notice blood in your urine, as this may be a sign of
kidney stones.

Very rare side effects: may affect up to 1 in 10,000 people
- hallucinations, memory loss, coma, neuroleptic malignant syndrome
(inability to move, sweating, fever, incontinence), status epilepticus
(prolonged or repeated seizures).
- breathing disorders, shortness of breath, inflammation of the lungs.
- inflammations of the pancreas (severe pain in the stomach or back)
- liver problems, kidney failure, increased blood levels of creatinine
(a waste product that your kidneys should normally remove).
- severe rashes or skin peeling (at the same time you may feel unwell or
develop a fever).
- abnormal muscle breakdown (you may feel pain or weakness in your
muscles) which can lead to kidney problems.
- swollen glands, blood disorders (reduction in the number of blood cells,
which can make infection more likely and can make you look pale, feel
tired and feverish, and bruise more easily).
- decreased sweating, overheating.
Reporting of side effects
If you get any side effects, talk to your doctor or pharmacist. This includes
any possible side effects not listed in this leaflet. You can also report side
effects directly via the Yellow Card Scheme, website
www.mhra.gov.uk/yellowcard. By reporting side effects you can help
provide more information on the safety of this medicine.
5. How to store Zonisamide
Keep this medicine out of the sight and reach of children.
Do not use this medicine after the expiry date which is stated on the carton
and blister after EXP. The expiry date refers to the last day of that month.
This medicine does not require any special storage conditions.
Do not throw away any medicines via wastewater or household waste. Ask
your pharmacist how to throw away medicines you no longer use. These
measures will help protect the environment.
6. Contents of the pack and other information
What Zonisamide capsules contain
- The active substance is zonisamide. Zonisamide 25 mg Hard Capsules
contain 25 mg of zonisamide. Zonisamide 50 mg Hard Capsules contain
50 mg zonisamide. Zonisamide 100 mg Hard Capsules contain 100 mg
zonisamide.
- The other ingredients are:
Capsule content: Microcrystalline cellulose, magnesium stearate.
Capsule shell: Gelatin, titanium dioxide (E171), sodium laurilsulfate,
purified water, black iron oxide (E172) (50 mg hard capsules),
Printing ink: Shellac, black iron oxide (E172) and potassium hydroxide.

What Zonisamide capsules look like and contents of the pack
Zonisamide 25 mg Hard Capsules
Contact your doctor as soon as possible if you:
White to off-white granular powder in hard capsules, size 4 (14.3 mm x
- have an unexplained skin rash, as this could develop into a more severe 5.31 mm), with a white to off white capsule body and a white to off-white
skin rash or skin peeling.
capsule cap. The cap is imprinted with “A730” in black ink.
- feel unusually tired or feverish, have a sore throat, swollen glands, or find Zonisamide 50 mg Hard Capsules
that you bruise more easily, as this may mean you have a blood disorder. White to off-white granular powder in hard capsules, size 3 (15.9 mm x
- have signs of increased acid level in the blood- headaches, drowsiness, 5.82 mm), with a white to off-white capsule body and a grey capsule cap.
shortness of breath and loss of appetite. Your doctor may need to
The cap is imprinted with “A735” in black ink.
monitor or treat this.
Zonisamide 100 mg Hard Capsules
White to off-white granular powder in hard capsules, size 1 (19.4 mm x
Your doctor may decide that you should stop using Zonisamide.
6.91 mm), with a white to off-white capsule body and a white to off-white
capsule cap. The cap is imprinted with “A740” in black ink.
The most common side effects of Zonisamide are mild. They occur during
the first month of treatment and usually decrease with continued
Zonisamide capsules are packaged in blisters supplied in boxes containing:
treatment. In children ages 6 - 17 years old, side effects were consistent with - 25 mg: 14, 28 or 56 hard capsules
those described below with the following exceptions: pneumonia,
- 50 mg: 14, 28 or 56 hard capsules
dehydration, sweating decreased (common) and abnormal liver enzymes
- 100 mg: 28, 56, 98 or 196 hard capsules.
(uncommon).
Not all pack sizes may be available.
Very common side effects: may affect more than 1 in 10 people
- agitation, irritability, confusion, depression
Marketing Authorisation Holder
- poor muscle coordination, dizziness, poor memory, sleepiness,
Dr. Reddy’s Laboratories (UK) Ltd., 6 Riverview Road, Beverley,
double vision
- loss of appetite, decreased blood levels of bicarbonate (a substance that East Yorkshire, HU17 0LD, United Kingdom
prevents your blood from becoming acidic)
Manufacturer
Balkanpharma - Dupnitsa AD, 3 Samokovsko Shosse Str., Dupnitsa 2600,
Common side effects: may affect up to 1 in 10 people
Bulgaria
- difficulty sleeping, strange or unusual thoughts, feeling anxious or
emotional.
- slowed thoughts, loss of concentration, speech abnormalities, abnormal This leaflet was last revised in 03/2016
skin sensation (pins and needles), tremor, involuntary movement of the
eyes.
- kidney stones.
- skin rashes, itching, allergic reactions, fever, tiredness, flu-like symptoms,
hair loss.
- ecchymosis (a small bruise caused by blood leaking from broken blood
vessels in the skin).
- loss of weight, nausea, indigestion, stomach pains, diarrhoea
(loose stools), constipation.
- swelling of the feet and legs.
Uncommon side effects: may affect up to 1 in 100 people
- anger, aggression, thoughts of suicide, suicide attempt.
- vomiting.
- gall bladder inflammation, gallstones.
- urinary stones.
- lung infection / inflammation, urinary tract infections.
- low blood potassium levels, convulsions/seizures.

Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.